NOTE : most NOAA sites down, but actually nautical charts remain operational :
http://www.nauticalcharts.noaa.gov
http://www.nauticalcharts.noaa.gov
Thursday, October 3, 2013
Seafloor scours hint at ancient Arctic ice sheet
A bathymetric map of the Arctic's Arlis Plateau, with sets of
different streamlined glacial lineations. The arrow marks the flow
direction of ancient ice sheets.
Credit: Frank Niessen, Alfred Wegener Institute
Credit: Frank Niessen, Alfred Wegener Institute
From LiveScience (by Becky Oskin)
Traces of immense prehistoric ice sheets discovered
When deep ice sheets chilled most of North America and Europe 20,000 years ago, Alaska and eastern Siberia remained remarkably ice-free, providing passage for America's first humans.
A map of the Arctic showing the location of the thick East Siberia ice sheet.
But before the explorers arrived, during earlier Pleistocene ice ages, an ice sheet more than half a mile (about 1 kilometer) thick jutted into the Arctic Ocean from Siberia, a new study finds.
Seafloor surveys near Wrangel Island (off the coast of Siberia) and the Arlis Plateau revealed deep scratches carved by glaciers and preserved in the seafloor.
There is more than one set of glacial grooves, and the researchers think at least four ice sheets existed, going back as far as 800,000 years.
"We knew of such scour marks from places like the Antarctic and Greenland," geologist Frank Niessen of the Alfred Wegener Institute in Germany said in a statement.
"They arise when large ice sheets become grounded on the ocean floor and then scrape over the ground like a plane with dozens of blades as they flow. The remarkable feature of our new map is that it indicates very accurately right off that there were four or more generations of ice masses, which in the past 800,000 years moved from the East Siberian Sea in a northeasterly direction far into the deep Arctic Ocean," said Niessen, the lead study author.
>>> geolocalization with the Marine GeoGarage <<< The ancient traces cover an area the size of Scandinavia.
The discovery is unique in the Arctic because the continental ice sheets in Greenland, Europe and North America never extended offshore, the researchers said.
[Photos of Melt: Glaciers Before and After]
"Previously, many scientists were convinced that mega-glaciations always took place on the continents — a fact that has also been proven for Greenland, North America and Scandinavia," Niessen said in the statement.
Though the scratches and glacial deposits preserved in the seafloor suggest there were four glaciations in this region of the Arctic, the researchers haven't yet matched the sediments with global coolings recorded in ice cores or ocean records.
But they can confirm that there was no big ice patch about 20,000 years ago, when scientists think the Bering Land Bridge, or Beringia, provided a refuge for animals during the great chill.
"With the exception of the last ice age 21,000 years ago, ice sheets formed repeatedly in the shallow areas of the Arctic Ocean," Niessen said.
"Our long-term goal is to reconstruct the exact chronology of the glaciations so that with the aid of the known temperature and ice data, the ice sheets can be modeled," Niessen said.
"On the basis of the models, we then hope to learn what climate conditions prevailed in Eastern Siberia during the ice ages and how, for example, the moisture distribution in the region evolved during the ice ages."
The findings were published Aug. 11 in the journal Nature Geoscience.
Wednesday, October 2, 2013
Geneq introduces sub-meter GNSS receiver for the Apple iPad and iPhone
Fully authorized and approved by Apple, the iSXBlue II GNSS implements an Apple proprietary Bluetooth authentication feature allowing the NMEA GNSS data to replace the internal GPS location of the iPad or iPhone.
Furthermore, a free SDK (software development kit) is available from Geneq to further utilize all the features of the iSXBlue II GNSS.
The iSXBlue II GNSS uses both GPS and GLONASS with SBAS (WAAS/EGNOS/MSAS/GAGAN) to attain 30cm/1 ft (RMS) accuracy in real-time using free SBAS corrections.
In addition to Apple iPads and iPhones, it connects wirelessly to any smartphone, handheld, tablet computer or notebook computer that is Bluetooth-compliant.
“The iSXBlue II GNSS is the first high-accuracy GNSS receiver in the world for the Apple iPad and iPhone, “ said Jean-Yves Lauture, product engineer, “and by implementing both GPS and GLONASS with SBAS, it provides iPad and iPhone users real-time, sub-meter accuracy around the world.”
With the ability to track 55 satellites (31 operational GPS, 24 operational GLONASS), the SXBlue II GNSS uses between 12 and 19 satellites in view at any time, providing superior performance when working under and around tree canopy, buildings and rugged terrain.
The next-generation iSXBlue II GNSS is the same, small, palm-sized unit as the SXBlue II GNSS and utilizes a small 2.7” diameter GNSS antenna.
The unit is completely waterproof (submersible), dustproof and ruggedized, with an IP-67 rating.
Its Class 2 Bluetooth 2.0 has a typical range of 15 meters, and is Apple-approved.
The internal, rechargeable, field replaceable Li-Ion battery has on-board LEDs let the user know how much battery life is left.
The operating temperature range of the iSXBlue II GNSS is -40°C (-40°F) to 85°C (185°F).
In addition to the built-in long-range Bluetooth transceiver, the iSXBlue II GNSS also has a standard DE-9 RS-232 port and a USB Type B port whose outputs are fully programmable up to 10Hz standard, and a 20Hz option.
Other optional features are L1 RTK for <2cm accuracy="" and="" base="" br="" output.="" real-time="" rtcm="" station="">
There is no need for post-processing or other sources of differential corrections as the iSXBlue II GNSS uses WAAS (North America), EGNOS (Europe), MSAS (Japan) and GAGAN (India) satellite corrections.
Users receive real-time, 30cm/1 foot positioning all day long.
The iSXBlue II GNSS is targeted at GPS/GIS mapping professionals in industries such as forestry, utility, agriculture, environmental and other natural resource industries in addition to local, state and federal government users.
About Geneq Inc.
For more than 40 years, Geneq has been a leading supplier of testing and measuring instruments in various fields of application.
For 20 years, Geneq has provided professional GPS mapping receivers and software products world-wide.
You can visit the SXBlue GPS website.
An unarmed approach to piracy
Intelligence solution relaying information about piracy and other serious maritime crime,
presented on digital nautical charts
Technology might allow some ships to leave the guns at home.
That doesn’t mean they will be defenseless.
The changing seascape of global piracy indicates that the technology to share and integrate information may prove to be as important for safe navigation as military support.
Modern piracy is here to stay.
And it’s no longer confined to the Gulf of Aden.
The latest hotspot is West Africa, where the oil-rich Gulf of Guinea is seeing a spike in the number of attacks.
Vulnerable areas include the waters off Nigeria, Ivory Coast, Ghana, Benin, Togo, Cameroon and Lagos.
A Paradigm \Shift in Global Piracy
According to Arild Nodland, CEO at Bergen Risk Solutions (BRS), global piracy is changing.
Somali piracy might still be the foremost threat in the minds of shipowners and operators, but a glance at the incident map will show it becoming less common.
According to Nodland, the decline in Somali piracy has been achieved by containment and deterrence tactics.
With piracy moving from Somalia to the Gulf of Guinea and further offshore, the pirates’ strategies are changing. “Nigerian pirates are using motherships.
They are using some of the same methods as the Somalian pirates,” said Nodland.
Not only is there a change in the pirates’ modus operandi, but also in their choice of targets, with kidnappings taking a backseat role.
Recently, there has been a rise in the number of oil-product tanker hijackings, according to Nodland.
Rather than kidnapping people, pirates hijack a tanker, steal the fuel cargo, transfer it onto a local tanker and get away with it.
“It’s an enormously lucrative trade,” Nodland said.
But it’s not just Africa that’s at risk.
Piracy is global.
In recent years countries from India and Indonesia to Peru and the Philippines have seen vessel hijackings and armed robbery in their waters.
Besides costing the shipping industry billions each year, piracy today puts the lives and wellbeing of thousands of seafarers at risk.
Piracy is all about armed robbery, assault, murder and even torture.
Armed guards onboard ships have proven to be an effective measure against piracy.
But what about complementary e-navigation based solutions that can help seafarers to avoid confrontation entirely?
South China Sea , 1 Sept 2010
E-Navigation to Combat the Piracy Threat
Research and the use of data can go a long way towards avoiding the scourge of the seas.
For Nodland, getting information out of Nigeria is a challenge, because “the oil companies and government tend to keep a lid on things. But we have an excellent network in the country that enables us to provide good data on maritime security,” he adds.
BRS uses Jeppesen’s Piracy Update software to help customers identify, understand and manage the risks associated with crime at sea.
It is based on intelligence from recognized and authoritative sources on global sea piracy.
BRS gathers, verifies and uploads this information five times a day during the week and once on weekends.
Piracy Update is used by mariners aboard vessels, as well as by owners, operators and insurers ashore.
Several national navies use it too.
Another feature of the software is the inclusion of weather information.
This is important because pirates can’t operate in certain weather conditions.
“The challenge is not lack of information but too much of it,” says Nodland.
“So one needs a system that can process then disseminate what is timely and relevant. Piracy Update’s filtering function allows us to select incidents and time frames that are relevant to our customers’ requirements.”
BRS uses Piracy Update every day to locate high-risk areas and to communicate this knowledge to customers.
“We use it when producing risk assessments for clients with a long-term outlook, such as drilling and seismic operators – and we use it to assist clients with a much shorter term requirement, for example ships in transit in the Gulf of Aden and the Indian Ocean,” said Nodland.
Piracy Update in Action
One example where Piracy Update helped provide valuable insight to lawyers, insurers, the owner, charterers and other parties involved, was when 14 hijackers armed with AK-47s and knives approached a 73,400-dwt Greek oil tanker on October 6, 2012.
The vessel was in the region to carry out two ship-to-ship transfers off Abidjan.
It had 30,000 tons of gas oil on board.
Before the second operation took place, the ship switched off all lights and sailed directly south without explanation.
A total of 24 Greek and Filipino crew were on board the vessel.
The vessel was forced to steam southeast and then northeast towards Nigeria.
Three days later the ship met a waiting vessel and the hijackers offloaded 2,600 metric tons of gasoline.
The vessel was released some 50 NM east of Lagos on October 9.
“Piracy Update quickly established a good overview of the geographical situation and also immediately showed us that this was an atypical attack, as it was carried out 350 nautical miles west of the pirates’ usual hunting grounds,” says Nodland.
“That made us uncertain at first; but when we used Piracy Update to compare this hijacking with what we knew about similar incidents, in terms of the modus operandi, type of ship being hijacked and cargo carried, we were soon able to tell the client what had happened, what the risks were to their vessel, cargo and crew, and what was likely to happen next.”
“When we plotted distances and calculated the ship’s speed from the point she was hijacked to where the pirates were likely to take her, we could also provide the owners with a rough timeframe for how long the hijacking was going to last,” said Nodland.
Piracy Update is delivered by Jeppesen and integrated with its other products — electronic navigation charts, ports database, weather and wave forecasts — allowing Nodland’s team to quickly plan a safe seaborne medical evacuation, which was thankfully unnecessary.
That said; Nodland emphasizes, “It is not a miracle tool. It cannot tell you where the pirates will take a hijacked ship, for example. So we rely on good intelligence analysts and experienced area specialists as well.”
Piracy Update may not be a miracle, but it does provide a sound technology that supports a non-military approach to combating modern piracy.
Links :
Tuesday, October 1, 2013
Brazil DHN update in the Marine GeoGarage
4 new charts and 4 charts have been updated since the last update
- 21300 DO CABO NORTE AO CABO MAGUARI NEW
- 1641 DA ENSEADA DO MAR VIRADO AO PORTO DE SÃO SEBASTIÂO
- 1645 CANAL DE SÃO SEBASTIÃO
- 1910 DA ILHA DE CORAL AO CABO DE SANTA MARTA GRANDE
- 2104 CANAL SÃO GONÇALO DA BARRA A PELOTAS NEW
- 4101B DE MANGABAL À ILHA DO COMANDAÍ NEW
- 4103B DA COSTA DO ITUQUI À ILHA DO MEIO NEW
- 4106B DA ILHA GRANDE EVA A MANAUS
- 200 DA ILHA DE MARACÁ À ILHA DO MACHADINHO
- 210 PROXIMIDADES DA BARRA NORTE DO RIO AMAZONAS
Don't forget to visit the NtM Notices to Mariners (Avisos aos Navegantes)
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